<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    div {
      line-height: 80px;
      padding-left: 50px;
      background-color: orange;
    }
  </style>
</head>

<body>
  <div id="box">
    <!-- <button>按钮</button> -->
    123456<span style="color:red; font-weight:bold;">APP</span>123456
  </div>

  <script>
    document.querySelector('#box').addEventListener('click', function (e) {
      // 用户点击的是谁，e.target 就指向谁
      // console.log(e.target)

      // e.currentTarget 表示当前“正在触发”事件的那个元素
      console.log(e.currentTarget)
    })
  </script>
</body>

</html>